In many fields of technology it is necessary to maintain a critical component or assembly in a controlled atmosphere. Exemplary of such technologies are optical communications and flat panel displays. See, for instance, U.S. Pat. No. 4,119,363, which discloses a hermetically sealed housing that contains a laser, with an optical fiber extending into the housing. See also U.S. Pat. No. 4,940,916, incorporated herein by reference, which pertains to field emission flat panel displays. Such displays require that the micropoint field emitters be located within a hermetically sealed enclosure. See also U.S. patent application Ser. No. 07/889,735, also incorporated by reference.
A known method of forming a hermetic enclosure involves solder bonding a piece part to another piece part (frequently to be called herein a "lid" and a "box", respectively), such that the desired enclosure results. However, there are problems associated with this method. For instance, prior art boxes and lids frequently are relatively costly, manufacturing yield typically is determined by the uniformity of wetting of the solder, and the presence of a solder bond places an upper limit on the temperature of any subsequent manufacturing operation.
In view of the economic significance of articles that comprise a hermetically sealed enclosure, a method of forming such an enclosure that does not exhibit the drawbacks of the prior art method would be highly desirable. This application discloses such a method, and articles made by the method.
Compression bonding is a known bonding technique. See, for instance, U.S. Pat. No. 4,937,653, which discloses compression bonding of IC chips to a Si wafer carrier that comprises textured bonding regions. See also Japanese patent document 54-54572/1979, which discloses a Si element that is thermally bonded to a metal pedestal (via a gold or gold alloy layer applied to a "rough" section of the pedestal), with the "roughness" due to indentations formed in the pedestal surface by blades.